Exercise Physiology Final
What are major causes of fatigue?
- Glycogen depletion - Acidosis of muscle - Failure to stimulate muscle at the neuromuscular junction
Which of the following are mechanisms of increased stroke volume after endurance training?
- increased plasma volume - increased filling time - increased LV wall thickness and chamber volume
Which respiratory exchange ratios (RERs) is typical for a resting individual?
0.78
Normal body fluid osmolality is approximately
300 mOsm/kg
The ATP-PCr system would be the primary ATP source for which event?
50 m Sprint
Define Myoglobin
A compound similar to hemoglobin, but found in muscle tissue, that carries oxygen from the cell membrane to the mitochondria
Define Hyperplasia
An increase in the number of cells in a tissue or organ
Which statements are true about myoglobin?
- Its function and pigment are similar to hemoglobin. - It is less abundant in type II muscle fibers. - It increases by 75 to 80% after aerobic training
All of these cause vasodilation
- Nitric Oxide - EDHF (endothelium-derived hyperpolarizing factor) - H+ accumulation
EPOC serves all of the following purposes
- Replenishes O2 stores in hemoglobin and myoglobin - Replenishes cytosolic ATP, PCr stores - Replenishes glycogen stores via lactate conversion
The pulmonary circulation encompasses all of these structures
- Tricuspid valve - Right ventricle - Pulmonary arteries
Anaerobic training leads to all of the following changes
- increased anaerobic power - type I fiber hypertrophy - decreased percentage of type I fibers in muscle
T3 and T4 are responsible for all of the following
- increasing size and number of mitochondria - increasing cellular metabolic rate - increasing FFA mobilization
Norepinephrine plays a role in all of these
- neural regulation of blood flow - endocrine regulation of blood flow - extrinsic regulation of blood flow
Which changes does occur in the blood after aerobic training?
- plasma volume increases - red blood cell production increases - hematocrit decreases
The equation for power is ____________. a. (force x distance)/time b. (time x distance)/force c. (time x force) d. distance
(force x distance)/time
Lactate produced during exercise can be utilized by which of the following tissues?
- Adjacent muscle fibers - Heart - Liver - Brain
A unit of measure for energy and heat
Calorie
Respond to changes in carbon dioxide (PCO2) and H+(pH) levels. When the levels increase, they send signals to the inspiratory center, activating the neural circuitry to increase the rate and depth of inspiration, which increases the removal of carbon dioxide and H+
Central Chemoreceptors
Sensory impulses that result in controlled and coordinated movements are integrated in the
Cerebellum
Nerves that primarily release acetylcholine as a neurotransmitter
Cholinergic
An increase in muscle size that results from repeated long-term resistance training
Chronic Hypertrophy
Maximal force development decreases progressively at higher speeds in _________ contractions
Concentric
Blood flow in muscles and other tissues is also under extrinsic control via the sympathetic nervous system which typically causes vessels to
Constrict
In which part of the cell does glycolysis occur?
Cytosol
A sheath of connective tissue that covers each muscle fiber
Endomysium
When pulmonary stretch receptors send a signal that triggers a shortened duration of inspiration, this is known as the
Hering-Breuer reflex
The family study that helped confirm that each individual responds differently to the same exercise stress
Heritage
Which region of the diencephalon oversees homeostatic control of blood pressure, heart rate, breathing, and body temperature?
Hypothalamus
Define Hypertrophy
Increase in the size or mass of an organ or body tissue
During high intensity sprints, what is the most specific cellular mechanism of fatigue?
Pi accumulation
A type of dynamic-action resistance training based on the theory that use of the stretch reflex during jumping will recruit additional motor units
Plyometrics
Under resting conditions, the ATP-PCr system plays which role?
Replenishing cellular ATP reserves
Training designed to increase strength, power, and muscular endurance`
Resistance Training
What nervous system prepares your body to face a crisis, regulating the fight-or-flight response?
Sympathetic Nervous System
Which one of these increases in direct proportion to exercise intensity?
Systolic blood pressure
Which is the correct order of events in a contraction?
T-tubule action potential, Ca2+ released, cross-bridging, Ca2+ gathered in
Strength
The ability of a muscle to exert force
Which of these statements is true about leg muscle fibers from an Olympic sprinter versus an Olympic marathon runner?
The amount of force generated by similar-sized muscle fibers is similar
Define Submaximal Endurance
The average absolute power output a person can maintain during a fixed period of time on a cycle ergometer, or the average speed or velocity a person can maintain during a fixed period of time
The maximal force a muscle or muscle group can generate is termed ____________. a. muscular power b. muscular endurance c. muscular strength d. muscular weight
c. Muscular Strength
During concentric contractions, increasing the speed of contraction will
decrease the force produced
After aerobic training, submaximal pulmonary ventilation will be _________, and maximal pulmonary ventilation will be ___________.
decreased, increased
As fitness improves, hematocrit typically
decreases
During endurance exercise, total peripheral resistance
decreases
Protein synthesis ___________ during exercise and ____________ after exercise.
decreases, increases
During prolonged exercise, T3 _______, while T4 _________.
decreases, plateaus
How does heat buildup in muscle contribute to fatigue?
hastens glycogen depletion
Type I muscle fibers
have a high oxidative capacity
Tupe II fibers
have more fibers per motor unit
The anterior pituitary is controlled by
hypothalamic hormones
The posterior pituitary is controlled by
hypothalamic nerve signals
Protein can serve as an energy substrate if
it is first converted to glucose
As submaximal exercise intensity increases, VO2
increases proportionally
The pneumotaxic center regulates inspiratory volume by ______
inhibiting inspiration
Smooth muscle is called
involuntary muscle and is found in the walls of most blood vessels
Cardiac muscle is
involuntary muscle and is found only in the heart
A disadvantage of direct calorimetry is that
the heat generated by exercise equipment must be taken into account
Training with no rest intervals, varying from high-intensity activity of moderate duration to low-intensity activity of extended duration
Continuous Training
Reflexes associated with Golgi tendon organs prevent skeletal muscles from
Contracting with too much force
Which receptors potential changes from -70 mV to -55 mV, what will happen?
An action potential will be generated
What is Needs Analysis?
An assessment of factors that will determine the specific training program appropriate for an individual
Define Chronic Hypertrophy
An increase in muscle size that results from repeated long-term resistance training
Metabolic reactions that result in the synthesis of molecules
Anabolism
Training that improves the efficiency of the anaerobic energy- producing systems and can increase muscular strength and tolerance for acid-base imbalances during high-intensity effort
Anaerobic Training
The increased VCO2 thought to result from excess carbon dioxide being released from bicarbonate buffering of lactic acid is the ____
Anaerobic threshold
The process of muscle contraction involves which ion?
Ca2+
Which of the following methods of CO2 transport in blood contributes to acid-base balance?
Carbonic acid/bicarbonate
The ability of the body to sustain prolonged exercise
Cardiorespiratory Endurance
Which group of hormones exerts metabolic and cardiovascular effects during exercise?
Catecholamines
Where do the highest levels of thought, interpretation, planning, analysis, cognition, and perception occur?
Cerebral (gray) Cortex
A hormone released by the gastrointestinal tract that signals the brain to suppress hunger
Cholecystokinin (CCK)
Which hormones act to suppress hunger?
Cholesystokinin (CCK), Peptide YY (PYY) and Insulin
Cells located between the sarcolemma and the basement membrane that help muscle cells adapt to growth, injury, and training
Satellite Cells
The job of an afferent neuron is to
Send impulses from the body to the brain
How many hormones does the anterior pituitary secrete?
Six
In the heat, blood flow will be redirected to the ______
Skin
While both the nervous and endocrine systems are critical for communication and coordination among body systems, the endocrine system responds more
Slowly but has longer-lasting effects
The brain activates muscles in the legs for running through the
Somatic Nervous System
The principle that a training program must stress the physiological systems critical for optimal performance in a given sport to achieve desired training adaptations in that sport
Specificity
The principle that physiological adaptations in response to physical training are highly specific to the nature of the training activity
Specificity of Training
When ADP accumulates, what is the effect on the rate of metabolic chemical reactions?
Speeds them up
The ability of a muscle to exert force
Strength
Plyometric training takes advantage of the
Stretch reflex
The average absolute power output a person can maintain during a fixed period of time on a cycle ergometer, or the average speed or velocity a person can maintain during a fixed period of time
Submaximal Endurance
Which of these sets of factors determines the rate of ATP production?
Substrate availabilty, enzyme activity
A series of three stimuli in rapid sequence, before complete muscle relaxation from the first stimulus, is called
Summation
The accumulation of multiple EPSPs on a postsynaptic cell is called
Summation
Metabolic enzyme activity can be increased by increasing the
Temperature
Which hormones promote muscle growth?
Testosterone and Growth Hormones
Which contractile result of rate coding will produce the most force?
Tetanus
Define Transient Hypertrophy
The "pumping up" (hypertrophy) of a muscle during a single exercise bout, resulting mainly from fluid accumulation in the interstitial and intracellular spaces of the muscle
Why is it necessary to have an action potential (electrical signal) in the muscle for contraction?
The SR will only release ca2+ if it has been electrically stimulated
Define Muscular Endurance
The ability of a muscle to resist fatigue
Define Cardiorespiratory Endurance
The ability of the body to sustain prolonged exercise
Define Sarcopenia
The loss of muscle mass associated with aging
Define Acetyl-CoA
The molecule produced from both carbohydrate and fat metabolism that enters the Krebs Cycle
Define the Principle of Progressive Overload
The overload principle that the training stimulus must be progressively increased as the body adapts to the current stimulus to maximize the benefits of a training program
Define the Principle of Variation
The principle that a training program must alternate high-intensity workouts with low-intensity workouts to help the body recover and achieve optimal training adaptation
Define the Principle of Specificity
The principle that a training program must stress the physiological systems critical for optimal performance in a given sport to achieve desired training adaptations in that sport
Define the Principle of Indidviduality
The principle that any training program must consider the specific needs and abilities of the person for whom it is designed
What is Specificity of Training?
The principle that physiological adaptations in response to physical training are highly specific to the nature of the training activity
Define Power
The product of Force and Velocity
Define Respiratory Exchange Ratio
The ratio of carbon dioxide expired to oxygen consumed at the level of the lungs
During _____________, a neuron can only be stimulated by a stronger-than-normal stimulus.
The relative refractory period
Define the Principle of REversibility
The theory that a training program must include a maintenance plan or the gains from training will be lost
What role do white blood cells play in the development of DOMS?
They secrete inflammatory substances that activate pain nerves in muscle
When we inhale, which of the following occurs as a result of the respiratory pump?
Thoracic vena cavae fill
Define High Responders
Those people in a population who show clear or exaggerated responses or adaptations to a stimulus
Define Low Responders
Those people in a population who show little or no response or adaptation to a stimulus
Removal of autogenic inhibition most likely plays a key role in "superhuman" feats of strength.
True
T/F: According to Dalton's Law, the partial pressures of nitrogen, oxygen, and carbon dioxide add up to atmospheric pressure
True
T/F: After aerobic training, blood flow through exercising muscles increases due to increased capillary formation and capillary recruitment.
True
T/F: After anaerobic training, the cross-sectional areas of type I, IIa, and IIx fibers increase.
True
T/F: After endurance training, stroke volume increases due to changes in preload, contractility, and afterload.
True
T/F: Aldosterone and ADH plays a major role in monitoring fluid levels and correcting imbalances
True
T/F: Cells contain between 2,000 and 10,000 hormone receptors of various types
True
T/F: Chemical buffers in the blood are only a short-term solution for blood acidosis after exercise.
True
T/F: Chemoreceptors in the aortic arch are less sensitive to changes in H+ concentrations and PCO2 than are the carotid chemoreceptors
True
T/F: Circulating white blood cell counts increase as muscle soreness increases.
True
T/F: During systole, the ventricles contract but dont eject their full blood volumes
True
T/F: Erythropoietin regulates red blood cell production and is extremely important to our adaptation to high-altitude training
True
T/F: Even though the volume of blood flowing through each circulation every minute is the same, much lower vascular pressures occur in the pulmonary circulation than in the systemic circulation.
True
T/F: Exercise-induced arterial hypoxemia occurs in 40 to 50% of elite athletes exercising at near-maximal intensities
True
T/F: Fartlek training is, in essence, a combination of continuous and interval training
True
T/F: Many scientists view cardiac output as the limiting factor for VO2max
True
T/F: Maximal heart rate is determined by age, not fitness status
True
T/F: Maximal oxygen consumption (VO2max) is limited primarily by the oxygen transport to the working muscles, not the available mitochondria and oxidative enzymes
True
T/F: Most researchers now prefer to use the term resting metabolic rate (RMR) instead of basal metabolic rate (BMR), because RMR is an easier measurement to take than BMR
True
T/F: Muscle Spindles supply information on the length and rate of change in length
True
T/F: When developing a program for someone who is just starting resistance training, a single set of resistance training exercises can be as effective as multiple sets for increasing muscle size and strength
True
T/F: With aerobic training, the lactate threshold moves up to a higher % VO2max.
True
The sum of all changes in the membrane potential must equal or exceed the threshold to cause sufficient depolarization to generate an action potential
True
Cardiac muscle fibers are most similar to which skeletal muscle fibers?
Type I
Glycogen depletion from muscle fiber types occurs in which order?
Type I, IIa, IIx
Define Autogenic Inhibition
Types of reflex inhibition of a motor neuron in response to excessive tension in the muscle fibers it supplies, as monitored by the Golgi tendon organs
A slow increase in VO2 during prolonged submaximal exercise at a constant power output
VO2 Drift
maximal cardiac output × maximal (a-v) O2 difference =
VO2max
The process of holding the breath and attempting to compress the contents of the abdominal and thoracic cavities, causing increased intra-abdominal and intrathoracic pressure
Valsalva Maneuver
The principle that a training program must alternate high-intensity workouts with low-intensity workouts to help the body recover and achieve optimal training adaptation
Variation
Accumulation of metabolic by-products in muscle (H+, CO2, heat) leads to
Vasodilation
The ratio between the volume of air expired or ventilated (VE) and the amount of oxygen consumed by the tissues (VO2) in a given amount of time is the ____
Ventilatory Equivalent for oxygen
Muscles increase the rate of force development
When motor units contract more synchronously
What situation is optimal for physical performance?
a low hematocrit with a normal or slightly elevated number of red blood cells
One day last week, Jenna went hiking in the woods and noticed that her heart beat faster and her respiration rate increased as she climbed some steep hills. Jenna was noticing ____________. a. chronic adaptations to physical activity b. diurnal variation c. the principle of periodization d. acute adaptations to physical activity
acute adaptations to physical activity
High-intensity interval training yields
aerobic fitness equal to that gained by chronic endurance training
If the rate of oxidative production of ATP is low, then
aerobic power is low
At the onset of strenuous exercise, what changes would you expect to see in venous O2 content and (a-V) o2 difference, respectively?
decrease, increase
resistance to blood being ejected from the left ventricles
afterload
Cardiovascular drift is associated with
decreased venous return
Nonsteroid hormones are characteristically
amino acid/protein based
If the ventilatory equivalent for oxygen starts to increase and at the same time the ventilatory equivalent for carbon dioxide does not increase, this means that
anaerobic metabolism is increasing
T/F: Acute adaptations are the ways in which the body responds over time to the stress of repeated exercise bouts
False
T/F: Aerobic interval training produces greater muscular adaptations than does continuous training
False
T/F: An (a-V) o2 difference of 16 mL O2/100 mL blood indicates a resting condition
False
T/F: As you increase the intensity of training, the frequency of the training sessions must also increase
False
T/F: Cardiorespiratory endurance is the ability of one muscle group to sustain prolonged exercise
False
T/F: Direct calorimetry is widely regarded as a useful tool for exercise measurements
False
T/F: During endurance exercise, diastolic blood pressure increases proportionally with exercise intensity while systolic blood pressure may actually decrease a little
False
T/F: Fiber splitting results from detraining and manifests as muscle atrophy.
False
T/F: For most athletes, training on a treadmill is the best way to improve VO2max values
False
T/F: Genetics is not a significant factor to consider when designing a training plan.
False
T/F: Given that atmospheric pressure is 760 mmHg, the partial pressure of oxygen is 105 mmHg
False
T/F: HIIT training increases maximal oxygen consumption in untrained individuals but has no effect on trained athletes
False
T/F: Heart enlargement as a result of endurance training is a medical risk and should be attended to immediately.
False
T/F: Height is one of the factors that affect total daily caloric expenditure
False
T/F: Immobilization has little effect on fiber cross-sectional area
False
T/F: Isometric training leads to more significant strength gains than from dynamic resistance training, contradicting early research findings
False
T/F: Resistance training, in combination with endurance training, appears to restrict improvement in aerobic power and may decrease short-term endurance
False
T/F: Resting and submaximal oxygen consumption greatly increases following endurance training
False
T/F: Sensory impulses that terminate in the spinal cord typically result in a conscious movement
False
T/F: Steroid hormones are lipid soluble and have difficulty crossing cell membranes
False
T/F: Strength development is optimized by many repetitions and low resistance, whereas muscular endurance is optimized by few repetitions and high resistance
False
T/F: Strength gains cannot occur unless there is an increase in muscle size.
False
T/F: Strength is synonymous with power
False
T/F: The blood's oxygen-carrying capacity is a limiting factor of performance in healthy people
False
T/F: The duration of rest intervals during training should be limited to 30 s at the most
False
T/F: The glycolytic system has a tremendous energy-yielding capacity, so it is the primary method of energy production during endurance events
False
T/F: The immediate increase in ventilation that occurs before the onset of exercise is stimulated by changes in blood CO2 and H+
False
T/F: The oxygen diffusion gradient from alveoli to capillary blood is ~40 mmHg
False
T/F: Transient hypertrophy results from increased protein synthesis and lasts about a week.
False
T/F: Type IIa fibers are the most frequently recruited muscle fibers
False
The same endurance is demonstrated at either 15 reps at 75% of 1RM or 1 rep at 100% 1RM
False
T/F: Calcium consumption affects a person's basal metabolic rate?
False, it does not
A small bundle of muscle fibers wrapped in a connective tissue sheath within a muscle
Fascicle
As glycogen stores run out, what substrate do muscles primarily rely on for ATP production?
Fat
Which energy substrate contains the most energy per gram?
Fat
An athlete with a high percentage of type II fibers would exhibit which characteristics?
Fewer mitochondria, lower oxidative enzymes
A person with bradycardia likely has ____________. a. abnormal cardiac function or a diseased heart b. a highly conditioned heart c. an extremely high resting heart rate d. either a or b
d. either a or b
Law stating that the net diffusion rate of a gas across a fluid membrane is proportional to the difference in partial pressure, proportional to the area of the membrane, and inversely proportional to the thickness of the membrane
Fick's Law
Which source of glucose is used preferentially by exercising muscle?
From muscle glycogenolysis
Which factor is most critical in determining the rate of pulmonary diffusion?
Gas partial pressure
Statement that accurately describes blood pressure?
Generates the force that drives blood flow
Which of these external factors plays the biggest role in determining ? a. training status b. genetics c. nutritional intake d. body composition
Genetics
A hormone secreted from the stomach and pancreas when the stomach is empty in order to stimulate hunger
Ghrelin
These hormone's secretion increase during exercise
Glucagon, Epinephrine, Norepinephrine and Cortisol
Taking into account both oxygen requirements and ATP yield, which substrate is more efficient, fat or glucose?
Glucose is more efficient
Increased reliance on fats for energy production during endurance activity, rather than stores of glycogen
Glycogen Sparing
Why do plasma glucose concentrations start to decline after prolonged endurance exercise?
Glycogen stores are depleted
Many marathon runners "hit the wall" around mile 20. What does this tell you about glycogen?
Glycogen stores are mostly depleted by mile 20
Senses the tension applied by muscle to its tendon, providing information about the strength of muscle contraction
Golgi tendon organ
An equation allowing one to calculate the inspired air volume from expired air volume, or expired air volume from inspired air volume
Haldane Transformation
The best determinant of the length of a rest/recovery interval is
Heart Rate
What does not cause vasodilation?
Increased local blood pressure
Define Glycogen Sparing
Increased reliance on fats for energy production during endurance activity, rather than stores of glycogen
Resistance training in elderly populations is especially helpful because
It can help prevent falls
Increased blood pressure during exercise has what effect on plasma volume?
It decreases due to increased capillary hydrostatic pressure
Which receptors would tell the brain that the elbow was fully extended but is now bending quickly?
Joint Kinesthetic Receptors
In a resting neuron, which ion gates are open?
K+ (Potassium)
The active contraction of the atria that completes the process of blood moving passively from the atria to the ventricles is sometimes called a
Kick
A series of chemical reactions that involve the complete oxidation of acetyl CoA and produce 2 mol of ATP along with hydrogen and carbon, which combine with oxygen to form H2O and CO2
Krebs Cycle
In the absence of oxygen, the final product of glycolysis is
Lactic Acid
What factor causes fatigue after 1 to 2 min of high-intensity exercise?
Lactic Acid accumulation
A hormone primarily secreted by fat cells that acts on receptors in the hypothalamus to decrease hunger
Leptin
Glycogen is stored in the _________ until needed
Liver and Muscle
Define Atrophy
Loss of size, or mass, of body tissue with disuse
Those people in a population who show little or no response or adaptation to a stimulus
Low Responders
During endurance exercise, fatigue correlates best with
Low glycogen stores
Which condition during exercise induces the Bohr effect?
Lower pH
The pulmonary circulation does not encompasses
Mitral valve
Norepinephrine concentrations increase at _____________ exercise intensities, and epinephrine concentrations increase at ______________ exercise intensities
Moderate, high
Carbohydrate oxidation yields ___ ATP per molecule of Oxygen consumed when compared to ATP yield per Oxygen molecule for fat
More
Which intracellular change likely contributes the most to increases in fiber size, cross-sectional area, and strength?
More Actin and Myosin Filaments
The somatic nervous system most specifically belongs to which division of the nervous system?
Motor
A single alpha-motor neuron and all the muscle cells (fibers) it innervates
Motor Unit
In the events lasting longer than a few seconds, glycogen stored in the _____ is the primary energy source for ATP synthesis
Muscle
Muscle hypertrophy occurs primarily as a result of an increase in
Muscle Cell Size
A sensory receptor located in the muscle that senses how much the muscle is stretched
Muscle Spindle
The ability of a muscle to resist fatigue
Muscular Endurance
The muscle's ability to repeatedly develop and sustain near-maximal forces
Muscular Endurance
What is the explosive aspect of strength?
Muscular Power
The fastest impulses travel on axons that are
Myelinated and large
A grouping of numerous sarcomeres
Myofibril
A compound similar to hemoglobin, but found in muscle tissue, that carries oxygen from the cell membrane to the mitochondria
Myoglobin
Thick filaments are primarily made of which protein?
Myosin
The process of plasmalemma depolarization involves which ion?
Na+
_____ is most important for depolarization.
Na+
Aldosterone release leads to
Na+ retention followed by water retention
Which ion transporter is engaged at rest to maintain resting membrane potential?
Na+-K+-ATPase pump
An assessment of factors that will determine the specific training program appropriate for an individual
Needs Analysis
How do products of a metabolic pathway typically help control the rate of the chemical reactions?
Negatively feed back on the rate-limiting enzyme
The electrical signal conducted along a neuron, which can be transmitted to another neuron or an end organ, such as a group of muscle fibers
Nerve Impulse
What is the term used to describe the phenomenon that occurs when oxygen supply does not increase as fast as oxygen need at the onset of exercise?
Oxygen Deficit
General sensory input from muscles and joints is processed in the
Parietal Lobe
The connective tissue sheath surrounding each muscle fasciculus
Perimysium
The gradual cycling of specificity, intensity, and volume of training to achieve peak levels of fitness for competition
Periodization
Sensitive primarily to blood changes in PO2 but also respond to changes in H+ concentration and PCO2. Sends signals to the inspiratory center to increase the rate and depth of inspiration
Peripheral Chemoreceptors
What is the Product of Force and Velocity?
Power
Rapid movement or ballistic-type training may be particularly effective in stimulating increases in motor unit
Rate Coding
Refers to the frequency of impulses sent to a muscle. Increased force can be generated through increase in either the number of muscle fibers recruited or the rate at which the impulses are sent
Rate Coding
After chronic endurance training, RER during submaximal exercise indicates that the body is
depending more on fat, less on carbohydrate for fuel
The loss of exercise capacity, strength, and performance after cessation of training is called
detraining
If dehydration causes hematocrit to rise to 60%, what is the consequence?
diminished exercise capacity due to impeded blood flow
When does atria and ventricles fill with blood?
during diastole
When is RER <0.7?
during gluconeogenesis from amino acids and fat
Muscle contraction that results in a charge in joint angle is called
dynamic contraction
labored or difficult breathing
dyspnea
Electrical stimulation provides the most benefit for muscle strength when
employed during immobilization after an injury
Secretion of nitric oxide is an example of
endothelial control of blood flow
Which of these is the correct order of skeletal muscle hierarchical organization, from largest structure to smallest structure?
entire muscle, muscle fasciculus, muscle fiber, myofibril
DOMS is ______________ the development of fiber hypertrophy.
essential for
If chemoreceptors stimulate an increase in breathing rate and depth, this occurs because
excess CO2 needs to be "blown off" (removed)
A low responder is someone who
experience little or no change after a change in training regimen
The internal intercostals are engaged during
forced expiration
Advanced weight lifters should particularly emphasize
free-weight resistance training
As RER values approach 1.0
glucose/glycogen metabolism is maximal
If muscle pH falls to 6.4, what occurs in the cell that promotes fatigue?
glycogen breakdown stops
Which of these is NOT a neural adaptation that may cause gains in strength? a. changes in the firing frequency or discharge rates of motor units b. additional motor unit recruitment, perhaps with synchronization c. reduction in coactivation of antagonist muscles d. gradually increased neurological inhibition of such mechanisms as the Golgi tendon organ
gradually increased neurological inhibition of such mechanisms as the Golgi tendon organ
A breathing rate or tidal volume greater than necessary for normal function
hyperventilation
In response to aerobic training, muscle fiber mitochondria
increase in size and number
During exercise, glucagon concentrations _________, and insulin concentrations __________.
increase, decrease
What will decrease stroke volume?
increased afterload
When neural and circulating norepinephrine lead to an increase in stroke volume, it is due to
increased contractility
The sympathetic nervous system would contribute to
increased heart rate
The pneumotaxic center regulates volume by
inhibiting inspiration
The exchange of gases between the blood and tissues
internal respiration
Norepinephrine does not play a role in
intrinsic regulation of blood flow
Renin is released when the
kidneys sense low blood volume and pressure
Why does aerobic performance continue to improve with training after VO2max has plateaued?
lactate threshold continues to increase
A key characteristic of steroid hormones is
lipid soluble
An example of a target cell for glucagon would be
liver cells
When PO2 is ~20 mmHg, what is myoglobin doing?
loading O2
Studies show that economy of effort is greatest in
long- and ultra-long-distance athletes
Maximal anaerobic capacity would involve
maximal ATP production from PCr
Which of the following statements correctly describes the change in cardiac output in response to aerobic training?
maximal cardiac output increases
VO2max =
maximal cardiac output × maximal (a-v) O2 difference
The signaling pathways that stimulate muscle protein synthesis are primarily turned on by
mechanical stretch of muscle cells
Strength is most accurately a property of the
motor system
Epimysium relates to entire muscle as endomysium relates to
muscle fiber
The adrenal gland secretes
non-steroid hormones that are amino-acid derivatives
During normal quiet breathing, the neurons in the expiratory respiratory center are`
not active
For a given plasma concentration, hormone effectiveness can be altered by the
number of cell receptors
The neuromuscular system is
one of the most responsive systems to training
Which of these is a major factor in muscle that limits further increases in VO2max ?
oxygen diffusion from capillary to mitochondria
Which of the following is not true about oxidative enzyme response to aerobic training? a. activity increases even after has plateaued b. exerts a glycogen-sparing effect in muscle c. can also be stimulated by high-intensity interval training d. phosphorylase and phosphofructokinase activities are particularly high
phosphorylase and phosphofructokinase activities are particularly high
Plasma volume increases during the first two weeks of aerobic training because
plasma protein synthesis increases
The degree to which the myocardium is stretched before it contracts, determined by factors such as central blood volume
preload
Which of the following statements explaining the increase in SV after aerobic training is correct?
preload and contractility increase, afterload decreases
Acetylcholine affects the sinoatrial node by
promoting hyperpolarization
The second heart sound heard through a stethoscope during auscultation indicates which event in the heart?
pulmonary and aortic valves closing
Hormone secretion is
pulsatile
Which mathematical factor that determines resistance has the most impact in the body?
radius of vessel
Aerobic power is defined as ____________. a. rate of energy release by cellular metabolic process that function without oxygen b. maximal capacity for aerobic resynthesis of ATP c. rate of energy release by cellular metabolic process that depend on oxygen d. maximal capacity of ATP-PCr system and anaerobic glycolytic system to produce ATP
rate of energy release by cellular metabolic process that depend on oxygen
Erythropoietin release is the primary stimulus for
red blood cell production
HIIT training increases the expression of the membrane transporters MCT1 and NHE1 which leads to improvements in _______________________. a. blood flow b. reduced accumulation of hydrogen ion c. glucose utilization d. calcium release
reduced accumulation of hydrogen ion
Based on breathing patterns immediately after exercise, postexercise breathing is most likely
regulated by blood pH, PCO2, and temperature
The respiratory zone in the lungs includes the
respiratory bronchioles
For sprint training, the most practical way to set the intensity of an interval is to
set a specific duration for a given distance
The speed of muscle fiber contraction is determined primarily by
spee of myosin ATPase
Isokinetic training ensures that
speed remains constant
The plasmalemma performs all of these functions except
storing Ca2+ ions to enable contraction
According to the size principle, which motor unit will be recruited first for a task?
the motor unit with the smallest motor neuron
A normal resting heart rate is determined by
the parasympathetic nervous system
The mechanical stretch of muscle cells primarily turn on
the signaling pathways that stimulate muscle protein synthesis
All of the following statements are true about type I fibers except
they appear white under a microscope
If a type I fiber and a type II fiber of the same size are stimulated side by side
they will generate the same amount of force
Why does (a-v) O2 difference increase after aerobic training?
tissue O2 extraction increases
T/F: After endurance training, a person's lactate threshold will occur at a higher rate of work than it did before training
true
T/F: The higher the initial state of conditioning, the smaller the relative improvement in VO2max for the same program of training
true
T/F: The right and left ventricles contract at the same time
true
If the intensity of a single bout of aerobic exercise continues to increase, but VO2max plateaus or decreases slightly, this means that
true VO2max has been reached
Compared to someone who can squat 75 kg, someone else who can squat 150 kg has
twice the strength
Immobilization primarily affects
type I fibers
As intensity increases, in which order are fibers recruited?
type I, type IIa, type IIx
Skeletal muscle is
voluntary muscle and is attached to and moves the skeleton
If blood pressure is relatively low, will it have an effect on stroke volume? Why?
yes, because the left ventricle pumps against less resistance
The maximum total O2-carrying capacity for a person with a blood volume of 5 L would be
~1 L O2
Aerobic training leads to _____________ in lactate threshold.
~30% increase
For aerobic metabolism, free fatty acids must be converted to acetyl-CoA via
β-oxidation
Define Summation
A series of three stimuli in rapid sequence, before complete muscle relaxation from the first stimulus
Define Plyometrics
A type of dynamic-action resistance training based on the theory that use of the stretch reflex during jumping will recruit additional motor units
An increase in plasma osmolality is the stimulus for release of
ADH
ATP + water + ATPase =
ADP + Pi + energy
is often caused by accumulation of fluid or H+.
Acute Muscle Soreness
Which of these substrate stores in the body can provide the most overall kilocalories?
Triglycerides
A tube-shaped protein that twists around actin strands, fitting in the groove between them
Tropomyosin
Nerves that primarily release norepinephrine as a neurotransmitter
Adrenergic
Training that improves the efficiency of the aerobic energy- producing systems and can improve cardiorespiratory endurance
Aerobic Training
A mineralocorticoid hormone secreted by the adrenal cortex that prevents dehydration by promoting renal absorption of sodium
Aldosterone
Which protein shields the myosin-binding site, preventing contraction from happening at rest?
Tropomyosin
Law stating that at a constant temperature, the number of gas molecules in a given volume depends on the pressure
Boyle's Gas Law
Sensory impulses that result in subconscious control of posture are integrated in the
Brain Stem
The _________ receive(s) all sensory input entering the brain
Diencephalon
A method that gauges the body's rate and quantity of energy production (calorimetry) by measuring the body's heat production
Direct Calorimetry
___ training is critical in developing fiber hypertrophy.
Eccentric
Training that involves a lengthening action to the muscle
Eccentric Training
A series of reactions inside mitochondria that use hydrogen ions to produce ATP, CO2, water, and heat
Electron Transport Chain
The process of bringing air into the lungs and the resulting exchange of gas between the alveoli and the capillary blood
External Respiration
A complex protein attached at regular intervals to actin strands and tropomyosin
Troponin
Which protein is sensitive to Ca2+ and thereby helps initiate contraction?
Troponin
By inserting rest intervals into anaerobic power training programs athletes
can perform a greater volume of work in session
An increase in heart rate during exercise to compensate for a decrease in stroke volume
cardiovascular drift
Resistance programs aimed at improving strength should involve
concentric and eccentric training
Which factor is considered to be the primary limiting determinant of VO2max?
central and peripheral cardiovascular function
Information originating in the brain that is transmitted to the cardiovascular, muscular, or pulmonary systems
central command
T/F: In most cases, stroke volume increases linearly up to VO2max
False
The body utilizes ______ oxygen when metabolizing carbohydrate compared to fat
Less
The process of converting protein into fatty acids
Lipogenesis
The breakdown of a triglyceride into its components is called
Lipolysis
Why are normalized VO2max values (i.e., ml O2 · kg-1 · min-1) greater in men than in women?
Men have more fat-free mass
The rate at which your body uses energy is referred to as your _______________
Metabolic Rate
The rate at which your body uses energy is referred to as your _______
Metabolic rate
In which part of the cell does oxidative phosphorylation occur?
Mitochondria
The most common fiber type alteration with heavy resistance training is
More type IIa, less type IIx
In general, whole-muscle hypertrophy in humans most likely results from
Mostly fiber hypertrophy with some fiber hyperplasia
How long is typical macrocyte?
One Year
T/F: Detraining has little effect on fiber cross-sectional area
True
T/F: Muscular strength varies throughout the full range of motion
True
T/F: Myoglobin "loading" happens at the same PO2 as hemoglobin "unloading."
True
T/F: Myosin ATPase is the enzyme that splits ATP to release energy for driving contraction
True
T/F: Steroid hormones diffuse rather easily through cell membrane
True
T/F: The average speed, or velocity, a swimmer can maintain during a fixed period of time is a good measure of his or her submaximal endurance
True
T/F: The function of the cavity between the pericardium and the heart is to hold fluid that reduces friction between the sac and the beating heart
True
T/F: The respiratory centers regulate breathing by stimulating contraction of skeletal muscles that control ventilation
True
T/F: Type II fibers have a fast form of ATPase, which means ATP is split more rapidly in type II fibers than in type I fibers
True
T/F: Type II fibers have more highly develped sarcoplasmic reticulum than do type I fibers
True
T/F: VO2max is synonymous with maximal aerobic power
True
Resistance training techniques designed for men
are equally appropriate for women's training
The role of the CNS in most types of fatigue is to limit exercise performance ____
as a protective mechanism
During diastole
atria and ventricles fill with blood
NADH molecules, formed in the _____________, cannot directly enter the mitochondria. a. nucleus b. sarcoplasm c. electron transport chain
b. sarcoplasm
Stretch receptor located within the cardiovascular system that senses changes in blood pressure
baroreceptor
Biological (chemical) reactions that produce energy
Bioenergetics
The mechanism that underlies preload's effects on stroke volume is the
Frank-Starling mechanism
_____ is most important for repolarization
K+
The basic functional unit of a myofibril
Sarcomere
Typical RMR values range from
1,200 to 1,400 kcal/day
During maximal exercise, respiratory muscles can receive up to what percentage of cardiac output?
15%
The PO2 in muscle mitochondria is roughly
2 mmHg
With DOMS, muscle enzyme concentrations may increase in the bloodstream by a factor of ________.
2 to 10 times
After an individual can lift a given weight at or above the desired number of repetitions for two consecutive training sessions, how much should the resistance be increased?
2 to 10%
FiO2=
20.93%
Which of the following is commonly used to estimate HRmax?
220 - age in years
The anaerobic glycolytic system would be the primary source of ATP for which running event?
800 m (1/2 mi) run
If your blood pressure is 110/70 mmHg, then your mean arterial pressure is (MAP= 2/3 DBP + 1/3 SBP)
83 mmHg
To train the anaerobic glycolytic system, what percentage of maximal heart rate should be attained?
85 to 100%
Define Cholecystokinin (CCK)
A hormone released by the gastrointestinal tract that signals the brain to suppress hunger
Define Athlete's Heart
A nonpathological enlarged heart, often found in endurance athletes, that results primarily from left ventricular hypertrophy in response to training
During the 400 m sprint (50-60 s long), which two metabolic pathways will be primarily involved?
ATP-PCr, glycolysis
In the presence of oxygen, the final product of glycolysis is
Acetyl-CoA
Which neurotransmitter binds to receptors on the motor end plate of a neuromuscular junction?
Acetylcholine
Rapid depolarization of the neuron's membrane lasting only about 1 ms
Action Potential
A nonpathological enlarged heart, often found in endurance athletes, that results primarily from left ventricular hypertrophy in response to training
Athlete's Heart
Loss of size, or mass, of body tissue with disuse
Atrophy
Types of reflex inhibition of a motor neuron in response to excessive tension in the muscle fibers it supplies, as monitored by the Golgi tendon organs
Autogenic Inhibition
Which region of the nerve cell integrates all incoming EPSPs and IPSPs?
Axon Hillock
Which of the following is associated with the parasympathetic nervous system?
Coronary arteriole constriction
A glucocorticoid that stimulates gluconeogenesis, fat mobilization, and protein catabolism
Cortisol
Training for more than one sport at the same time, or training multiple fitness components (such as endurance, strength, and flexibility) within the same period
Cross-Training
A decrease in the electrical potential across a membrane, such as when the inside of a neuron becomes less negative relative to the outside
Depolarization
Which phase of cardiac cycle is the longest?
Diastole
Which of the following is responsible for lowering the activation energy of a chemical reaction?
Enzyme Activity
Define mTOR
Enzyme that controls the rate of protein synthesis within the myofibrils after resistance training
The outer connective tissue that surrounds an entire muscle, holding it together
Epimysium
Which of the following is not an adrenal hormone?
Erythropoietin
The sequence that triggers a muscle fiber to contract
Excitation Contraction Coupling
A decline in arterial PO2 and arterial oxygen saturation during maximal or near-maximal exercise
Exercise-Induced Arterial Hypoxemia
The most important element in determining gains in muscle strength and mass appears to be
Exercising Muscles to Failure
A key characteristic of prostaglandins is that they
Exert their effects locally
Which of these is a consequence of low plasma volume?
Heart strain increases
The percentage of cells or formed elements in the total blood volume, more than 99% of cells or formed elements made up of red blood cells
Hematocrit
The law stating that gases dissolve in liquids in proportion to their partial pressures, depending also on their solubilities in the specific fluids and on the temperature
Henry's Law
Those people in a population who show clear or exaggerated responses or adaptations to a stimulus
High Responders
Which of the following is a response associated with increasing oxidative metabolism in an exercising muscle?
High heart rate
An increase in the number of cells in a tissue or organ
Hyperplasia
An increase in the electrical potential across a membrane
Hyperpolarization
Inhibitory postsynaptic potentials (IPSPs) lead to which response?
Hyperpolarization
Increase in the size or mass of an organ or body tissue
Hypertrophy
A method of estimating energy expenditure (calorimetry) by measuring respiratory gases
Indirect Calorimetry
The principle that any training program must consider the specific needs and abilities of the person for whom it is designed
Individuality
Which hormone increases the use of glucose, thereby lowering blood glucose levels
Insulin
Training that involves repeated brief, fast-paced exercise bouts with short rest intervals between bouts
Interval Training
An end organ that responds to change in mechanical stress, such as stretch, compression or distension
Mechanoreceptors
Why does a sarcomere that is too short or too stretched produce less force?
Not as many cross-bridges can form
If the net effect of all graded potentials is hyperpolarization, what will occur?
Nothing will occur
Oxygen deficit is incurred when
O2 demand > O2 consumption in early exercise
When the oxyhemoglobin curve shifts during exercise, what is the result?
O2 unloading becomes easier at the muscles
Neurons in the _________ let us consciously control movement of our skeletal muscles
Primary Motor Cortex
The overload principle that the training stimulus must be progressively increased as the body adapts to the current stimulus to maximize the benefits of a training program
Progressive
About 10% of the body's total oxygen consumption during heavy exercise can occur in the _________ muscle(s)
Respiratory
Respiratory muscles are directly controlled by motor neurons coming from
Respiratory Centers
The ratio of carbon dioxide expired to oxygen consumed at the level of the lungs
Respiratory Exchange Ratio
Passive movement of blood through the central circulation as a function of pressure changes during breathing
Respiratory Pump
The theory that a training program must include a maintenance plan or the gains from training will be lost
Reversibility
An increased PCO2 stimulates the inspiratory center to increase respiration to
Rid the body of excess CO2 and minimize pH changes
Heat EAMCs are most effectively treated using
Salt solution ingestion
A muscle fiber's cell membrane, a selectively permeable lipid layer coated by proteins
Sarcolemma
The loss of muscle mass associated with aging
Sarcopenia
Glycogen is stored in which region of a muscle fiber?
Sarcoplasm
The gelatin-like interior of a muscle fiber
Sarcoplasm
Ca2+ ions (essential for contraction) are stored in the
Sarcoplasmic Reticulum
Define Periodization
The gradual cycling of specificity, intensity, and volume of training to achieve peak levels of fitness for competition
A minimum amount of stimulus needed to elicit a response. Also, the minimum depolarization required to produce an action potential in neurons
Threshold
The membrane potential at which an action potential will definitely occur is the
Threshold
Which hormones increase the rate of cellular metabolism and the rate of contractility of the heart?
Thyroxine (T4) and Triiodothyronine (T3)
If you sit and breathe quietly into a spirometer, which lung volume is being recorded?
Tidal Volume
An array of proteins that stabilize the myosin filaments
Titin
The resistance to the flow of blood through the entire systemic circulation. (TPR)
Total Peripheral Resistance
Resistance Training
Training designed to increase strength, power, and muscular endurance
Define Cross-Training
Training for more than one sport at the same time, or training multiple fitness components (such as endurance, strength, and flexibility) within the same period
Define Aerobic Training
Training that improves the efficiency of the aerobic energy- producing systems and can improve cardiorespiratory endurance
Define Anaerobic Training
Training that improves the efficiency of the anaerobic energy- producing systems and can increase muscular strength and tolerance for acid-base imbalances during high-intensity effort
Define Eccentric Training
Training that involves a lengthening action to the muscle
Define Interval Training
Training that involves repeated brief, fast-paced exercise bouts with short rest intervals between bouts
Define Continuous Training
Training with no rest intervals, varying from high-intensity activity of moderate duration to low-intensity activity of extended duration
The "pumping up" (hypertrophy) of a muscle during a single exercise bout, resulting mainly from fluid accumulation in the interstitial and intracellular spaces of the muscle
Transient Hypertrophy
Which sarcomere structure reveals the most information about the intensity of eccentric workouts?
Z-Disk
A slower rate of glycogen utilization is
a beneficial adaptation conferred by aerobic training
When an increased amount of a specific hormone causes a decrease in the number of cell receptors available to it, the cell
becomes less sensitive to that hormone
The most effective buffer in the body is
bicarbonate
ATP is required for
both muscle contraction and muscle relaxation
Compared to fat molecules, glucose molecules contain _____ carbon atoms.
fewer
Increased red blood cell concentration by increased production of cells
hematopoiesis
A relative (not absolute) increase in the cellular content per unit of blood volume, resulting from a reduction in plasma volume
hemoconcentration
Which is not an important predictor of a successful endurance athlete?
high type II fiber percentage
Compared to untrained individuals, trained endurance athletes have
higher maximal stroke volumes
Higher levels of succinate dehydrogenase in a muscle would indicate
higher oxidative capacity
During exercise, the oxygen diffusion capacity increases dramatically because
lower venous O2 content increases the PO2 gradient
The pulmonary veins travel from the _____ to the_____
lungs, left atrium
Enzyme that controls the rate of protein synthesis within the myofibrils after resistance training
mTOR
During moderate exercise in the heat, which vascular beds receive the most blood flow?
muscle, skin
When motor units contract more synchronously,
muscles increase the rate of force development
The velocity of a nerve impulse transmission is primarily determined by
myelination and diameter of the neurons
The rate-pressure product is an index of
myocardial metabolism
The best way to establish the intensity of a distance interval is to
use a heart rate monitor
Up to a certain point, ventilation increases during exercise in direct proportion to the rate of work being performed. Beyond this point, ventilation increases disproportionately as the body tries to clear excess CO2. This point is the ___
ventilatory threshold
The span between the QRS complex and the T wave represents which phase of the cardiac cycle?
ventricular systole
The anchoring membrane that attaches to the lungs themselves is the
visceral pleura
The primary purpose of ADH is to promote
water retention
Muscle glycogen metabolism is disproportionally high
when exercise intensity is high
Passive vasodilation arises from
withdrawal of sympathetic influence on blood vessels